. >>> the war next door, is the obama administration downplaying the danger along the u.s.-mexico border? tonight, an exclusive nbc investigation. >>> and young hero, news about the brave teen that the whole world is pulling for. nightly news begins now. >>> good evening, there is every reason to believe the live television audience watching the vp debate tonight will be every bit as large as the last presidential debate, and because that debate was something of a game-changer, as it turned out, the stakes going into tonight are higher for two men from similar backgrounds, who are very different. for starters, this is the broadest age difference of any debate. our political team is in place tonight, our coverage includes our nbc polling numbers out just tonight on this race we want to begin with nbc's ron mott in danville, kentucky, tonight, good evening. >> reporter: hey, brian, to you, vice president joe biden will be there at that table, paul ryan the other table. congressman ryan comes into this debate, riding the republican wave of momentum the forward progress is what